Picturesque cave (6)
I believe the answer is:
grotto
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">picturesque cave</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for grotto that I've seen before include "Fancy cave" , "Attractive natural, or artificial, cave" , "In company (with); over length of" , "Cavern" , "(Imitation) cave" .)